Wow, you scored -Ã‚Â you just got a great deal on your airfare – say, $200 roundtrip. You’re especially jazzed because you knowÃ‚Â finding cheap flights at peak times of the year is a whole lot harder.

So if a family of four each checks a bag, that’s – whoa – $200. Not good.

And if your bag is overweight (generally above 50lbs) that can cost you as much as $100 one-way – and that’s in addition to the regular checked-baggage fee.

Don’t Miss That Trip

Non-refundable tickets (the kind most of us buy because they’re cheap) have whopping penalties of $150 (domestic) and $250 (international) roundtrip on most airlines.

This means you’ll lose a hefty portion (if not all) of the value of your original ticket not to mention the premium you’ll pay for the new last minute ticket price.

A better way to handle last minute changes is trying the $50 fee on some airlines for confirmed standby.

Ouch. Thanks for Nothing, Spirit

My advice? Pack light and use a carryon. Carryon bags are still free on most airlines – no thanks to Spirit Airlines carryon baggage precendent (there a carryon will set you back from $20 to $45 a piece).

Want Comfort? It’ll Cost You

Inflight fees can add up, too. I’ll call these “comfort fees” because they’re for amenities that are nice to have, though not strictly necessary.

Want to work on the plane? Wi-fi will cost you: the price generally depends on the length of the flight – $6 to $13 is typical.

Of course on some airlines you can pay a cut in line fee to make sure your overstuffed carryon has some bin space and there is always an option for extra legroom or confirmed seats for a fee (the latter if you don’t have airline elite status).

Hoping to nap on a plane, and looking for a pillow and blanket? Be prepared to fork over $7 for these airline amenities on JetBlue and US Airways (on the upside, they’re yours to keep).

Food, Glorious, Food

Hungry? I’ll bet, since there’s no free lunch in any airline’s coach class anymore (well, starting this fall, anyway, when the last holdout, Continental, drops this perk). And, on most airlines, those tasty fattening snacks will set you back anywhere from a couple of bucks for a cookie to close to $10 for a salad.Ã‚Â My advice is to pack your own lunch for the plane – everybody’s doing it.

If you do wish to buy something to eat or maybe a cocktail, forget about cash – mostairlines now require credit cards for all onboard purchases.

Don’t Make That Call!

Say you’re not so hot with computers and you figure you’ll make your reservation by phone instead? Think twice: most airlines now charge for that privilege – anywhere from $10 to $25. It could be worse though: European discounter Ryanair charges you for a call, or even to check-in online, plus they levy a somewhat mysterious “administration fee” just to make a reservation.

Fees You May Never Know About

The most hidden of fees are the so-called “peak travel date” surcharges, and that’s because these surcharges are rolled into your ticket. It is not an option like a bag fee, where you check a bag or not. If you fly on a date your airline has designated as a peak travel date, you will pay.

And they are hard to avoid.

See the FareCompare Peak Travel Date Surcharge Chart, and note that most of the summer is covered (through August 22); however, you can also clearly see that Tuesdays and WednesdaysÃ‚Â are the cheapest days to fly because they have the cheapest surcharges – $10 each-way – which is a lot better than the $30 each-way surcharges imposed on Sundays.

Obviously, fly the cheapest days – and just so you know, Tuesdays and Wednesdays are usually the cheapest days to fly year-round, surcharges or not.

So, the next time you snag that real-deep discount, don’t forget to factor in the other airline fees before you head for the airport. We want you to be prepared for your flight trip so the only thing that flys off is the plane–and not your temper.